Machine for bending and working wire



Jan. 4, 1966 E. STEGMANN MACHINE FOR BENDING AND WORKING WIRE 8 Sheets-Sheet 1 Filed Dec. 24, 1962 lll f IIII.L

INVENTOR. ERA/57 STEGMANN FIG.

4 T TORNEKS.

Jan. 4, 1966 E. STEGMNNN MAQHINE FOR BENDING AND WORKING WIRE 8 Sheets-Sheet 2 Filed Dec. 24, 1962 F 2 INVENTOR.

ERA/5T STEG'MA/VN Jan. 4, 1966 E. sTEMANN 3,227,195

MACHINE FOR BENDING AND WORKING WIRE Filed Dec. 24, 1962 8 Sheets-Sheet 3 INVENTOR. ERNST STE'G'MAN/V A T TORNE'KS'I Jan. 4, 1966 E, STEGM NN 3,227,195

MACHINE FOR BENDING AND WORKING WIRE Filed Dec. 24, 1962 8 Sheets-Sheet 4 mum 1N VENTOR. ERA/5 T STEGMA NN FI 4 fiwww A TI'ORNEYS.

Jan. 4, 1966 E. STEGMANN 3,227,195

MACHINE FOR BENDING AND WORKING WIRE Filed Dec. 24, 1962 8 Sheets-Sheet 5 ERNS T STE'GAMNN haww 7M Jan. 4, 1966 E. STEGMANN MACHINE FOR BENDING AND WORKING WIRE 8 Sheets-Sheet 6 Filed Dec. 24, 1962 INVENTOR. [2/15 7' STE'GMAAM/ ATTOQNEYS.

Jan. 4, 1966 E. STEGMANN 3,227,195

MACHINE FOR BENDING AND WORKING WIRE Filed Dec- 24, 1962 8 Sheets-Sheet '7 HQ 8 D F1614 FIGIS F F INVENTOR.

, ERA/5T SIEGAM V'V WW/Emu A TTORIVEKS.

Jan. 4, 1966 E. STEGMANN 3,227,195

MACHINE FOR BENDING AND WORKING WIRE Filed Dec. 24, 1962 .ZMiWiiM wimiw FIGZZ a Sheets-Sheet 8 F K326 F K327 1 N VEN TOR. ERA/5 7' 5 TEGMA IVN A TTOEA/EKL United States Patent 3,227,195 MACHINE FOR BENDING AND WORKING WIRE Ernst Stegmann, Reutlingen, Germany, assignor to Rheinstahl Hiittenwerlre Aktiengesellschaft, Essen, Germany Filed Dec. 24, 1962, Ser. No. 247,479 Claims priority, application Germany, Dec. 27, 1961, St 18,706 4 Claims. (Cl. 140-103) My present invention relates to improvements in machines for working and bending wire, in particular machines for fabricating double-leg springs.

In the present state of the art, continually closer finishing tolerances and an ever increasing multiplicity and variety of forms for the most diversified applications are required from spring manufacturers. This applies in particular to single-leg and double-leg springs, i.e. springs having angled ends of which either or both have to be deformed. So far such springs have had to be manufactured manually, with the aid of auxiliary devices, in a complicated and time-consuming way and manner, i.e. uneconomically.

Such drawbacks, inadequacy and inconvenience are eliminated by my present invention. The machine disclosed herein comprises, in known manner, a feeding, straightening and shearing attachment through which are made available pieces of wire of adjustable lengths for the purpose of further treatment. The machine according to the invention is distinguished by the fact that it additionally comprises an adjustable automatic attach ment for the leg bending operation and for forwarding the bent leg springs, and at least one adjustable, exchangeable and automatically acting attachment for one or more leg working operations, such as the operation of lug or eye bending and a leg winding operation. This machine is further characterized in that the steps necessary for making the singleor double-leg springs are carried out in successive working cycles.

One form of the present invention is shown by way of example in the accompanying drawings, in which FIG. 1 is a front elevation of the entire machine,

FIG. 2 is a side elevation thereof seen from the right,

FIG. 3 is a section on the line 33 of FIG. 1,

FIG. 4 is a front elevation of the leg-bending and transport station as well as of two working stations,

FIG. 5 is a longitudinal section through the control means,

FIGS. 6 and 7 are elevation views, partly in section,

of two different working stations,

FIGS. 8 to 11 illustrate the various steps required for making a double-leg spring comprising hooked ends,

FIGS. 12 and 13 depict the manufacture of a doubleleg spring of which the intermediate portions of the legs are provided with turns or windings, the leg portions are bent at an obtuse angle relatively to each other, and the legs have their ends bent in the form of a hook; and

FIGS. 14 to 27 show various forms of double-leg springs made by the machine of the present invention.

Referring to FIGS. 1, 2 and 3, the. machine comprises a column 1 on which is mountedwthe housing 2 which has a removable wall 2' (FIG. 2) and is closed in front by a swing door 2" (FIGS. 2 and- 3). On one side of column 1 is disposed the oil container 3 (FIGS. 1 to 3) on which is mounted the hydraulic unit comprising the oil pump 4, known per se and thus not further shown, and the high-pressure container 5. The hydraulic unit is provided with a liquid-filter (not shown), a built-in airfilter, a pressure regulating valve and a manometer, and is driven by an electric motor. (not shown).

On the other side of'column 1 is disposed the electric motor 6 (FIG. 1) which is connectable through a cable to a source of electric power. Motor 6 transmits its ice rotary movement through the drive belt 7 to the worm gearing 8 (FIG. 1), and thence through V-belts 9 to the horizontal main shaft 10 which is rotatably mounted in housing 2. The drive of shaft 10 is under the influence of an electromagnetic coupling which, being known per se, is not shown in the drawing. On one end of shaft 10 is mounted a handwheel 11 which drives shaft 10 through free-wheeling catches and is inactive when shaft 10 is rotating. Shaft 10 is a spline shaft over its entire length (FIG. 3), which permits the setting without play, of the control means mounted thereon and which will be described later.

The end of main shaft 10 remote from handwheel 11 is ope-ratively connected through a bevel gearing (not shown) which runs in an oilbath, to drive the disc 12 (FIG. 1) that is mounted outside of housing 2. Disc 12 is formed on one side with a diametric guide groove 13 in which is engaged a pin 15 (FIG. 1) provided on the adjustable link 14. By changing the adjustable fixed position of pin 15, the angular displacement of disc 12 is adaptable to the selected feed length of the wire to be worked.

Numeral. 16 designates a vertical support positioned outside of housing 2 and on which are arranged two rows of horizontahstaggered guide rollers 17. To support 16 is connected, in a manner not further shown, the horizontal carrier 18 which also is provided with two rows of vertical, staggered guide rollers 18a for the wire to be worked. From the guide rollers 17 of support 16 the work wire-which, for example, is unwound from a coil (not shown)moves between the two conveyor discs 19 and is advanced thereby through the guide body 20 (FIG. 4) to the shearing knife 21 (FIGS. 1 and 4) disposed, in a manner not further shown, vertically movable in the knife holder 22. Knife 21 is operated by a cam disc 21' which is mounted on the shaft 21" (FIG. 1). Knife 21 and the actuating means therefor are disposed within a frame 23 (FIG. 1). The latter is provided on its backside with guide means which are engaged in corresponding horizontal T-shaped guide grooves 25, 25" provided in the tool post 24 (FIGS. 1 and 3) whereby frame 23 may be horizontally moved and located, with respect to the feed elements of the wire to be worked, for the requisite length of wire. Shaft 21 on which is mounted cam disc 21' is oscillated by a control lever 26 of which the end remote from shaft 21" is hingedly connected to a piston rod 28 which is axially movable in oil cylinder 27. Both ends of cylinder 27 are connected through conduits 29 to cylinder 30 which is under the influence of a cam disc 31 (FIG. 3) mounted on main shaft 10.

To the ceiling of housing 2 is attached, in a manner not further shown, the bracket 32 on which is situated the vertical oil cylinder 33 which is connected at both ends to the oil feed line 34 that communicates with the hydraulic unit and is controlled by control valves.

In oil cylinder 33, there is axially movable the piston rod 35 whose lower end carries a pair of tongues forming wire clamping means 36 through which, as may be seen from FIGS. 1 and 4', is passed the wire D to be worked. The tongue lengths are selected in accordance with the length of the cross-web of the legsprings. On both sides of the tongues there are provided stops or anvils 37 (FIGS. 1, 4, Sand 9) ata bending station, and which coact with the tongues and are horizontally adjustable and locatable in the guide grooves 25 of the tool post24.

Below the tongues 36 and spaced from each other are arranged two wire coiling working stations I and II (FIGS. 1 and 4), positioned on a wall 38 provided inside the housing 2. Station I, as shown in FIGS. 1, 4 and 6, comprises two spaced bearing housings 38 disposed in the same horizontal plane, in each of which is rotatably supported a hollow shaft 39, said hollow shafts being coaxial lying in the same horizontal plane. Each of the shafts 39 carries a pinion 40 keyed to the midpoint thereof, which pinions mesh with the racks 40'. Each of the adjacent ends of the hollow shafts 39 is provided with a dog plate 41, and each dog plate is provided with an eccentrically disposed driving pin 42. In each of the hollow shafts 39, there is disposed an axially movable driving pin or mandrel 42. Each mandrel 42 carries a cross-pin 43 adjacent its outer end, each of which pins is engaged in a guide slot 44 of the adjacent end of a respective two-arm control lever 45. The other ends of the levers 45 are angled towards each other and provided with rollers 46 which engage the disc cams 48 fixed to the gear wheels 47. The latter are driven via the gear wheel 49 keyed to the control shaft 48". The racks 40' are fixed to the piston rods of respective oil cylinders 50 which, in a manner not further shown, are connected to the hydraulic unit. Said cylinders 50 are controlled by the valve 59 (FIG. which in turn is controlled by the disc cam 51 which is fixed to control shaft 48'.

Working station II (FIGS. 1, 4 and 7) comprises two coaxial bearing bodies 51 positioned in the same horizontal plane and which rotatably support the shaft 52 on which is keyed a pinion 53 disposed between the bearing bodies 51. Pinion 53 meshes with a rack 54 which, in a manner not further shown, is connected to the piston rod 55 which is axially movable in an oil cylinder 56 (FIGS. 4 and 5). The latter communicates with the hydraulic unit in a manner not further shown.

Shaft 52 transmits its rotation through back gears 56', provided at both ends thereof, to pinions 58 each keyed to a respective tubular shaft 57. Each hollow shaft 57 carries at one end a dog plate 59 which is provided with an eccentric driving pin 60. In each of the hollow shafts 57 is axially movable a bending mandrel 61. The ends of the mandrels 61 remote from the dog plates 59 are provided, as may be seen from FIGS. 4 and 7, with an adjustable and locatable holder 62 on which is disposed a cam roller 63 destined to be engaged in a channel guide rail 64. Circular discs 65 are connected to reciprocable guide rods 66, and have connected thereto, by screws 67, discs 68 (FIGS. 4 and 7) which correspond in diameter with the discs 65 and carry the guide rails 64. Discs 65 are angularly adjustable relative to discs 68. The guide rods 66 are axially movable in bearings 69 (FIG. 7) and carry rollers engaged with levers 71 which are swingably mounted on a common axle 70 (FIG. 7). Tension springs 72 are connected to the outer ends of levers 71, and the latter are acted on by pressure links 73 close to the axle 70, their ends remote from the levers 71, links 73 are pivotally interconnected by a pin 74 on which is mounted a pressure roller 75 with which coacts a plate cam 76 which is detachably connected to the disc 77 mounted on the control shaft 48'.

As shown in FIG. 5, three plate cams 78, 78 and 78" spaced axially from each other are mounted on control shaft 48' and are operatively connected to the oil pressure cylinders 79, 79' and 79". The oil pressure cylinders 79 and 79", respectively, each communicate at one end, through conduits with the hydraulic unit 3 to 5 and, at the other end, through a conduit 33" with the upper and lower end, respectively, of oil pressure cylinder 33. Together with oil pressure cylinder 79', the two conduits 34, 34 leading to oil pressure cylinder 33 are connected to the conduits 33".

The oil pressure cylinders 50 of station I, of which only one is visible in FIG. 5, communicate through the oil feed lines 50' with oil pressure cylinders 50 which latter connected to the hydraulic unit 3 to 5 and are equipped with valves which are operable by a plate cam 51 (FIG. 5) mounted on control shaft 48.'

Station II is controlled by a plate cam 81 mounted on control shaft 48'.

The mode of operation of the machine described is as follows:

After knife holder 22 carrying knife 21, and the feed elements for the wire D, have been set initially to the desired wire length, the corresponding wire clamping means 36 have been inserted, the stops 37 coacting with the latter have been set with respect thereto, the two working stations I and II have been brought to their positions required for the operation in question, the control elements have been set according to the various operational steps and working cycles, and the motor 6 for driving main shaft as well as the motor (not shown) for operating the hydraulic unit have been switched on, the wire to be worked is cut to the desired length, being passed (as shown in FIGS. 1, 4 and 8), through the wire clamping means 36 and then sheared off by the knife 6 which is actuated from the hydraulic unit. By means of the plate cam 78 mounted on control shaft 48 (FIG. 5), the valve for oil feed line 34 (FIG. 5) is opened so that oil flows from below into cylinder 33 and acts on the piston 33' (FIG. 5) mounted on piston rod 35. The latter, and thus also the tongues 36 clamping the wire D, are thereby drawn from the position shown in FIG. 8 into the position shown in FIG. 9, whereby on wire D and within the tongues 36 are formed a cross-web and two parallel legs. Plate cam 78' then moves out of the range of the control valve and the flow of oil through conduit 34 to oil cylinder 33 is interrupted. Then the valve controlling the conduit 34' is opened by the action of the plate cam mounted on control shaft 48', oil flows from above into cylinder 33, and piston rod with the tongues 36, which clamp the wire bent in U-shape, is moved downwardly, and the wire then is fed to station I (FIG. 4) whereby the free wire ends, as may be seen from FIG. 10, will be situated between the bending mandrels 42' and the dog pins 42. Under the influence of the plate cam 43 mounted on control shaft 48', valve 50' then is opened, and oil starts to flow into the cylinders 50 (FIG. 6) whereby rack is moved and the hollow shafts 39 are rotated together with the dog plates 41 and the dog pins or mandrels 42. Thereby the free ends of the two wire legs are turned about the stationary bending mandrel 42' and bent in the form of hooks, as may be seen from FIG. 11. Under the influence of the cam discs 48, the control levers then withdraw the bend ing mandrels 42' so that the hooked ends of the doubleleg springs are released.

Upon completion of the operation described in bending station I, the valve provided on oil cylinder 79 (FIG. 5) is opened by plate cam 78 which is seated on control shaft 48', and oil flows from above into cylinder 33 and the work is passed to station II by the tongues 36, whereby the two wire legs are provided with a plurality of turns at their midportions as may be seen from FIG. 12. Said windings are produced in the same manner as has been described with reference to station I, with the only difference that the hollow shafts 57 are driven from a common shaft 52 through back-gears 56. Shaft 52 is actuated by rack 54 which is connected to piston rod that is axially movable in oil cylinder 56.

By correspondingly adjusting the discs which carry the guide rails 64 (FIGS. 4 and 7) wire windings of more or less pitch may be obtained.

By reason of the fact that, during the coiling operation, the wire to be worked has to be subjected to a certain tension, plate cam 73 which coacts with cylinder 79' (FIG. 5) and is mounted on control shaft 48 has to regulate said tension. This is attained by closing the valves coacting with the oil cylinders 79, 79" (FIG. 5).

In order to permit the production of a variety of wire windings with the aid of a relatively small feed of rack 54 which actuates the working elements, the winding ele ments on station II are driven via back-gears 56, as may be seen in FIGS. 4 and 6.

The machine described is eminently suited for the automatic production of double-leg springs such as are shown in FIGS. 14 to 27, but also single-leg springs having the most diversified windings may be made with the machine just as well. l

I claim:

1. Apparatus for fiorming wire springs including a median portion and a leg extending from at least one end of the median portion, said apparatus comprising, in combination, a rotatable control shaft; driving means for rotating said shaft; a relatively elongated carrier longitudinally reciprocable between a wire receiving station, a wire bending station and at least one wirecoiling station; operating means reciprocating said carrier; jwire clamping means on said carrier; means for feeding straight wire to said wire clamping means when said carrier is in the wire receiving station; wire cutting means arranged to sever an adjustable preselected length of the fed wire so as to provide a straight piece of wire having a median portion clamped in said clamping means; stationary anvil means at the bending station and laterally closely adjacent the path of travel of said clamping means; said anvil means, as said carrier is moved in one direction to said bending station, engaging the wire projecting from said clamping means to bend at least one wire leg at an angle to said median portion; rotatable means,including a hen-ding mandrel, at said Wire coiling station; said carrier moving in the opposite direction from said bending station to said coiling station to feed the clamped wire, leg first, to said coiling station; actuating means operable to project said mandrel to engage the wire legs and then to rotate said rotatable means to coil the wire legs; and control means on said control shaft controlling cyclical and sequential operation: of said feeding means, said cutting means, said operating means and said actuating means.

2. Apparatus for forming wire springs, as claimed in claim 1, in which said operating means for reciprocating said carrier comprises a fluid pressure actuator; and valves controlling operation of said actuator in reversed directions; said control means including cams controlling said valves.

.3. Apparatus for forming wire springs, as claimed in claim 2, in which said rotatable means and bending mandrel at said wire coiling station form an eye on the end of the leg of the wire; a second wire coiling station positioned beyond said first mentioned wire coiling station in the direction of movement of said carrier in said opposite direction, said second wire coiling station including rotatable means and a bending mandrel reciprocable axially of said rotatable means; and actuating means at said second wire coiling station operable to project the mandrel thereat axially to engage the wire leg and to rotate the rotatable means at'said second wire coiling station to form plural turns in the wire leg between said median portion and said end thereof; said control means controlling operation of said actuating means and said second wire coiling station.

4. Apparatus for forming Wire springs, as claimed in claim 3, in which the actuating means at each wire coiling station comprises a fluid pressure actuator reciprocating a rack engaged with a gear connected to rotate with said rotatable means, and cam and lever means for reciprocating said bending mandrels; each of said rotatable means including an annular plate concentric with the bending mandrel and having the bending mandrel projectable axially the-rethrough, each annular plate having a pin eccentrically fixed on its face to cooperate with said bending mandrel in coiling the wire leg.

References Cited by the Examiner UNITED STATES PATENTS 344,247 6/1886 Cawley l03 841,634 1/1907 Crouch 140-103 1,192,631 7/1916 Hick 140103 1,192,655 7/1916 Lyons 140-103 2,868,237 1/1959 Larkin 140-71 3,049,156 8/1962 Livermore 14071 FOREIGN PATENTS 800,690 8/1958 Great Britain.

CHARLES W. LANHAM, Primary Examiner. 

1. APPARATUS FOR FORMING WIRE SPRINGS INCLUDING A MEDIAN PORTION AND A LEG EXTENDING FROM AT LEAST ONE END OF THE MEDIAN PORTION, SAID APPARATUS COMPRISING, IN COMBINATION, A ROTATABLE CONTROL SHAFT; DRIVING MEANS FOR ROTATING SAID SHAFT; A RELATIVELY ELONGATED CARRIER LONGITUDINALLY RECIPROCABLE BETWEEN A WIRE RECEIVING STATION, A WIRE BENDING STATION AND AT LEAST ONE WIRE COILING STATION; OPERATING MEANS RECIPROCATING SAID CARRIER; WIRE CLAMPING MEANS ON SAID CARRIER; MEANS FOR FEEDING STRAIGHT WIRE TO SAID WIRE CLAMPING MEANS WHEN SAID CARRIER IS IN THE WIRE RECEIVING STATION; WIRE CUTTING MEANS ARRANGED SO SEVER AN ADJUSTABLE PRESELECTED LENGTH OF THE FED WIRE SO AS TO PROVIDE A STRAIGHT PIECE OF WIRE HAVING A MEDIAN PORTION CLAMPED IN SAID CLAMPING MEANS; STATIONARY ANVIL MEANS AT THE BENDING STATION AND LATERALLY CLOSELY ADJACENT THE PATH OF TRAVEL OF SAID CLAMPING MEANS; SAID ANVIL MEANS, AS SAID CARRIER IS MOVED IN ONE DIRECTION TO SAID BENDING STATION, ENGAGING THE WIRE PROJECTING FROM SAID CLAMPING MEANS TO BEND AT LEAST ONE WIRE LEG AT AN ANGLE TO SAID MEDIAN PORTION; ROTATABLE MEANS, INCLUDING A BENDING MANDREL, AT SAID WIRE COILING STATION; SAID CARRIER MOVING IN THE OPPOSITE DIRECTION FROM SAID BENDING STATION TO SAID COILING STATION TO FEED THE CLAMPED WIRE, LEG FIRST, TO SAID COILING STATION TO FEED THE CLAMPED WIRE, ABLE TO PROJECT SAID MANDREL TO ENGAGE THE WIRE LEGS AND THEN TO ROTATE SAID ROTATABLE MEANS TO COIL THE WIRE LEGS; AND CONTROL MANS ON SAID CONTROL SHAFT CONTROLLING CYCLICAL AND SEQUENTIAL OPERATION OF SAID FEEDING MEANS, SAID CUTTING MEANS, SAID OPERATING MEANS AND SAID ACTUATING MEANS. 